For this equation
E= (-C/r) + D(-r/P)
(Where c, D, and P are constants)
Do the following procedure:
1. Differentiate E with respect to r and set the resulting expression equal to zero.
2. Solve for r0 in terms of C, D and P.
Here is where I am at in the problem:
I have obtained a derivative (and I'm looking for conformation that this is the correct derivative):
E' = C/r2 + (D(-r/P)lnD)(-1/P).
Then I set E equal to 0: 0= C/r2 + (D(-r/P)lnD)(-1/P)
Now I need to solve for r0 in terms of C, D and P. At this point I'm stuck. Either I don't have the algebra skills or I got the derivative wrong.
A derivative is found.